Applicant's own prior Canadian Pat. No. 889,808, entitled: "STRAPPING" and issued Jan. 4, 1972, describes a reinforcing flexible weftless tape in which the individual strands or yarns are made of synthetic resin fiber yarns, such as polyamide, polyethylene, polypropylene and the like. The tapes obtained in accordance with this Patent are designed to replace steel strapping and are used around a container and tied by a buckle or the like. Another use of such tape is as cargo slings. Such tape is too thick to be permanently adhered to corrugated board or carton in high-speed folding cartons or corrugated cardboard-making machinery, so as to obtain permanentlyreinforced containers made of such materials.